Contents distribution system and distribution server and display terminal of contents distribution system

ABSTRACT

In a contents distribution system for distributing contents from a distribution server to a display terminal through a transmission path, the distribution server detects a region in which a character is displayed from an image of video contents, generates an image of a high resolution of the detected region as character information for use in confirming a character displayed in the detected region and text data obtained by character read and distributes the generated character information with the video contents multiplexed to the display terminal, and the display terminal presents the character information received from the distribution server.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a system for distributing videocontents from a distribution server to a user's display terminal througha transmission path and, more particularly, to a contents distributionsystem for distributing contents to such a display terminal whosedisplay unit is small as a portable communication terminal, adistribution server and a display terminal thereof, and a contentsdistribution program.

[0003] 2. Description of the Related Art

[0004]FIG. 13 is a block diagram showing a structure of a conventionalvideo distribution system, in which a video distribution server 60 fordistributing video distributes video contents through a transmissionpath 30 and a user's video display terminal 70 receives and presents thevideo contents.

[0005] Japanese Patent Laying-Open (Kokai) No. 2000-32441 proposes atechnique of extracting telop information from television broadcastingreceived by a television receiver and transmitting and displaying theinformation to and on a still picture display terminal such as aremote-controlled terminal, thereby exhibiting character information tohave high quality.

[0006] Since telop information often contains such important informationfor understanding stories and contents at the time of viewing andlistening to video as telop in a news program and telop informationincluding superimposition of a movie, it is effective to present theinformation to users by using high-quality images easy to read.

[0007] Although not included in the above-described conventionaltechniques, extraction of not only telop information but also othercharacter information than telop is useful which exists in common scenessuch as a product name written on a product shown in a commercial film,characters on a signboard and a mark in the background of a drama.

[0008] Although the above-described conventional art disclosed inJapanese Patent Laying-Open (Kokai) No. 2000-324416 targets commontelevision broadcasting, the recent speed-up of the Internet, speed-upof radio communication in particular, enables users to view accumulatedvideo clips such as film advertisement and music promotion video througha PC at home or a mobile phone used outdoors. Distribution of live videois also conducted by distributing video taken by a camera called Webcamera which is disposed at a sightseeing spot or on a road through theInternet.

[0009] Although distributing such video without modification needs acommunication path of an extremely wide band, image compression andcoding techniques enable reduction of the amount of information. Withthe Internet whose band is approximately 64 kbps, for example, viewingvideo can be realized by distributing compressed video and decoding thesame by a terminal having received it.

[0010] For transmitting video at a bit rate as low as 64 kbps, however,video is coded with its resolution reduced or its quality degraded andthen transmitted to a portable terminal or a PC at home. Thus reducingthe resolution or degrading image quality results in making characterinformation contained in the video unclear to be extremely hard to read.

[0011] As described above, character information includes informationcrucial for video viewing, so that when the character informationbecomes hard to read, it might hinder video viewing.

[0012] As described in the foregoing, the conventional art has thefollowing problems.

[0013] There have conventionally existed no technique of, at the time ofdistributing video contents at a low bit rate, extracting characterinformation including telop information, coding the information to havehigh quality, distributing the coded information and having a user'sterminal display the same. The conventional art disclosed in JapanesePatent Laying-Open (Kokai) No. 2000-324416, for example, extracts telopfrom common television broadcasting received, while it fails to extracttelop from video contents reproduced by a portable communicationterminal or the like and distributed at a low bit rate becausecharacters are distributed being unclear.

SUMMARY OF THE INVENTION

[0014] An object of the present invention is to eliminate theshortcomings of the above-described conventional techniques and providea contents distribution system in which a reception side displayterminal is capable of clearly displaying characters of video contentsdistributed at a low bit rate, a distribution server and a displayterminal thereof, and a contents distribution program.

[0015] According to the first aspect of the invention, a contentsdistribution system for distributing contents from a distribution serverto a display terminal, wherein

[0016] the distribution server detects a region in which a character isdisplayed from an image of video contents, generates characterinformation for use in confirming the character displayed in the regiondetected and distributes the character information generated to thedisplay terminal.

[0017] In the preferred construction, the distribution server generatesan image of the region detected as the character information of thevideo contents.

[0018] In another preferred construction, the distribution servergenerates text data of the character displayed in the region detected asthe character information of the video contents by character read.

[0019] In another preferred construction, when a plurality of regions inwhich characters are displayed are detected from the image of the videocontents, the distribution server accepts designation of the region fromthe display terminal and distributes the character information generatedfrom the region designated to the display terminal.

[0020] In another preferred construction, the distribution serverdistributes the video contents to the display terminal simultaneouslywith the character information of the video contents, and the displayterminal presents the character information of the video contentsreceived from the distribution server together with the video contentsreceived simultaneously.

[0021] In another preferred construction, the distribution servermultiplexes the character information of the video contents and thevideo contents and distributes the multiplexed contents to the displayterminal.

[0022] In another preferred construction, the display terminal receives,from the distribution server, character information of the videocontents received from an external broadcasting station and presents thecharacter information of the video contents together with the videocontents.

[0023] In another preferred construction, the character information ofthe video contents includes character subsidiary information indicativeof features of the character displayed in the image of the videocontents, and the display terminal presents the character information ofthe video contents received from the distribution server based on thecharacter subsidiary information included in the character information.

[0024] In another preferred construction, the character subsidiaryinformation of the video contents includes information about a position,in the image of the video contents, of the region detected from theimage.

[0025] In another preferred construction, the character subsidiaryinformation of the video contents includes information about a layoutstructure of the character displayed in the image of the video contents.

[0026] According to the second aspect of the invention, a distributionserver for distributing contents to a display terminal, comprises

[0027] means for detecting a region in which a character is displayedfrom an image of video contents,

[0028] means for generating character information for use in confirmingthe character displayed in the region detected, and

[0029] means for distributing the character information generated to thedisplay terminal.

[0030] In the preferred construction, the server may further comprisemeans for, when a plurality of regions in which characters are displayedare detected from the image of the video contents, accepting designationof the region from the display terminal,

[0031] thereby distributing the character information generated in theregion designated to the display terminal.

[0032] In another preferred construction, the server may furthercomprise means for distributing the video contents to the displayterminal simultaneously with the character information of the videocontents.

[0033] In another preferred construction, the server may furthercomprise means for multiplexing the character information of the videocontents and the video contents and distributing the multiplexedcontents to the display terminal.

[0034] In another preferred construction, the server may furthercomprise means for generating an image of the region detected as thecharacter information of the video contents, and means for reducing thesize of an image of the video contents to be distributed to the displayterminal to a designated size,

[0035] thereby distributing the image generated as the characterinformation with quality higher than the quality of the video contentswhose image size is reduced to the display terminal together with thevideo contents reduced.

[0036] In another preferred construction, the server may furthercomprise means for generating an image of the region detected as thecharacter information of the video contents.

[0037] In another preferred construction, the server may furthercomprise means for generating an image obtained by making the regiondetected into a binary image as the character information of the videocontents.

[0038] In another preferred construction, the server may furthercomprise means for generating text data of the character displayed inthe region detected as the character information of the video contentsby character read.

[0039] In another preferred construction, the server may furthercomprise means for obtaining text data of the character displayed in theregion detected by character read, and means for generating atranslation which is obtained by translating the text data obtained bythe character read into a designated language as the characterinformation of the video contents.

[0040] In another preferred construction, the server may furthercomprise means for identifying features of a character displayed in theimage of the video contents,

[0041] thereby distributing, as character subsidiary information,information about features of the character identified so as to beincluded in the character information of the video contents to thedisplay terminal.

[0042] In another preferred construction, the server may furthercomprise means for recording the video contents and the characterinformation of the video contents, and means responsive to a requestfrom the display terminal for distributing the video contents and thecharacter information of the video contents requested to the displayterminal.

[0043] According to the third aspect of the invention, a displayterminal for presenting contents distributed from a distribution server,comprises

[0044] means for receiving character information for use in confirming acharacter displayed in an image of video contents from the distributionserver, and

[0045] means for presenting the character information received.

[0046] In the preferred construction, the display terminal may furthercomprise means for accepting, from the distribution server, anotification that a plurality of regions in which characters aredisplayed are detected from the image of the video contents, and meansfor notifying the region selected by a user from among the plurality ofregions detected to the distribution server,

[0047] thereby receiving the character information for use in confirminga character displayed in the region selected from the distributionserver.

[0048] In another preferred construction, the character information ofthe video contents is an image of a region in which a character isdisplayed in the image of the video contents.

[0049] In another preferred construction, the display terminal mayfurther comprise means for obtaining, from the image of the characterinformation by character read, text data of a character indicated in thecharacter information received and presenting the obtained data.

[0050] In another preferred construction, the character information ofthe video contents is text data of a character displayed in the image ofthe video contents.

[0051] In another preferred construction, the display terminal mayfurther comprise means for simultaneously receiving the characterinformation of the video contents and the video contents in questionfrom the distribution server, and means for presenting both thecharacter information and the video contents received.

[0052] In another preferred construction, the display terminal mayfurther comprise means for receiving the character information of thevideo contents and the video content in question which are multiplexedand distributed from the distribution server.

[0053] In another preferred construction, the display terminal mayfurther comprise means for receiving, from the distribution server, thecharacter information of the video contents received from an externalbroadcasting station and presenting the character information of thevideo contents together with the video contents.

[0054] In another preferred construction, the character information ofthe video contents includes character subsidiary information indicativeof features of the character displayed in the image of the videocontents, and which further comprises means for presenting the characterinformation of the video contents received from the distribution serverbased on the character subsidiary information included in the characterinformation.

[0055] In another preferred construction, the character subsidiaryinformation includes information about a position, in the image of thevideo contents, of a region in which a character in the image isdisplayed, and which further comprises means for presenting the videocontents with the region where the character is displayed which isindicated in the character subsidiary information erased.

[0056] In another preferred construction, the display terminal mayfurther comprise means for instructing the distribution server totransmit or not to transmit the character information.

[0057] According to another aspect of the invention, a display terminalfor presenting video contents, comprises means for detecting a region inwhich a character is displayed from an image of video contents,

[0058] means for generating character information for use in confirmingthe character displayed in the region detected, and means for presentingthe character information generated.

[0059] In the preferred construction, the display terminal furthercomprises means for presenting the character information of the videocontents in question together with the video contents.

[0060] In another preferred construction, the display terminal furthercomprises means for simultaneously displaying the character informationof the video contents and the video contents in separate windows on adisplay screen.

[0061] In another preferred construction, the display terminal furthercomprises means for simultaneously displaying, in an area in which thevideo contents are displayed on the display screen, characterinformation of the video contents.

[0062] In another preferred construction, the display terminal is aportable communication terminal.

[0063] According to another aspect of the invention, a contentsdistribution program for distributing contents to a display terminal bycontrolling a computer, comprising the functions of

[0064] detecting a region in which a character is displayed from animage of video contents,

[0065] generating character information for use in confirming thecharacter displayed in the region detected, and

[0066] distributing the character information generated to the displayterminal together with the video contents.

[0067] According to a further aspect of the invention, a contentsdistribution program for presenting contents distributed from adistribution server by controlling a computer, comprising the functionsof

[0068] receiving character information for use in confirming a characterdisplayed in an image of video contents from the distribution servertogether with the video contents, and

[0069] presenting the character information received together with thevideo contents received.

[0070] Other objects, features and advantages of the present inventionwill become clear from the detailed description given herebelow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The present invention will be understood more fully from thedetailed description given herebelow and from the accompanying drawingsof the preferred embodiment of the invention, which, however, should notbe taken to be limitative to the invention, but are for explanation andunderstanding only.

[0072] In the drawings:

[0073]FIG. 1 is a block diagram showing a structure of a contentsdistribution system according to a first embodiment of the presentinvention;

[0074]FIG. 2 is a flow chart for use in explaining operation of adistribution server of the first embodiment of the present invention;

[0075]FIG. 3 is a flow chart for use in explaining operation of adisplay terminal of the first embodiment of the present invention;

[0076]FIG. 4 is a block diagram showing a structure of a contentsdistribution system according to a second embodiment of the presentinvention;

[0077]FIG. 5 is a flow chart for use in explaining operation of adistribution server of the second embodiment of the present invention;

[0078]FIG. 6 is a flow chart for use in explaining operation of adisplay terminal of the second embodiment of the present invention;

[0079]FIG. 7 is a diagram for use in explaining character regionextraction according to the second embodiment of the present invention;

[0080]FIG. 8 is a diagram for use in explaining a video display schemeat the display terminal according to the second embodiment of thepresent invention;

[0081]FIG. 9 is a block diagram showing a structure of a contentsdistribution system according to a third embodiment of the presentinvention;

[0082]FIG. 10 is a flow chart for use in explaining operation of adisplay terminal of the third embodiment of the present invention;

[0083]FIG. 11 is a block diagram showing a structure of a contentsdistribution system according to a fourth embodiment of the presentinvention;

[0084]FIG. 12 is a flow chart for use in explaining operation of adistribution server according to the fourth embodiment of the presentinvention; and

[0085]FIG. 13 is a block diagram showing a structure of a conventionalvideo contents distribution system.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0086] The preferred embodiment of the present invention will bediscussed hereinafter in detail with reference to the accompanyingdrawings. In the following description, numerous specific details areset forth in order to provide a thorough understanding of the presentinvention. It will be obvious, however, to those skilled in the art thatthe present invention may be practiced without these specific details.In other instance, well-known structures are not shown in detail inorder to unnecessary obscure the present invention.

[0087]FIG. 1 is a block diagram showing a structure of a contentsdistribution system according to a first embodiment of the presentinvention, which also shows a structure of a distribution server 10 anda display terminal 20 of the present embodiment.

[0088] With reference to FIG. 1, the distribution server 10 of thepresent embodiment, which is realized by a program-controlled CPU or thelike, includes a video input unit 11, a video coding unit 12, acharacter extraction unit 13, a video transmission unit 14 and acharacter transmission unit 15. The display terminal 20 of the presentembodiment, which is realized by a program-controlled CPU or the like,includes a video reception unit 21, a video decoding unit 22, a videodisplay unit 23, a character reception unit 24, a character decodingunit 25 and a character display unit 26.

[0089] Video contents targeted by the distribution server 10 may be livecontents of television broadcasting and the like or video contents whichare already coded and accumulated such as movie preview video.

[0090] Although no specific limitation is set on a transmission path 30connecting the distribution server 10 and the display terminal 20,description will be made here as an example assuming that a generalradio line for a mobile phone, a PHS or the like, or a general telephoneline for an ISDN or the like is used to have a bit rate of 64 kbps to384 kbps.

[0091]FIG. 2 is a flow chart for use in explaining operation of thedistribution server 10 according to the present embodiment, while FIG. 3is a flow chart for use in explaining operation of the display terminal20 according to the present embodiment.

[0092] In the distribution server 10 of the present embodiment, thevideo input unit 11 receives input of video contents (Step 201), and thecharacter extraction unit 13 detects a region in which a character isdisplayed (character region) from the video contents to generatecharacter information for use in confirming the character (Step 202).Then, the video contents are coded by the video coding unit 12 (Step203), the coded video contents are transmitted by the video transmissionunit 14 to the display terminal 20 and at the same time, the charactertransmission unit 15 transmits the character information to the displayterminal 20 (Step 204).

[0093] By means of the video reception unit 21, the display terminal 20receives the video information (video contents) which is transmittedfrom the transmission server 10 and receives the character informationby means of the character reception unit 24 (Step 301). Then, decode thevideo contents by the video decoding unit 22 and decode the characterinformation by the character decoding unit 25 (Step 302). Then, displaythe video contents by the video display unit 23 and display thecharacter information by the character display unit 26 to present themto a user (Step 303). As a result the user of the display terminal 20 isallowed to view the video information and the character information.

[0094] Although in the present embodiment, as a transmission path fortransmitting video contents and character information from thedistribution server 10 to the display terminal 20, the commontransmission path 30 is used, the transmission path is not necessarilylimited to the common transmission path 30. Other than the system oftransmitting video contents and character information using packetswitching of the same mobile phone, possible is, for example, a systemof transmitting only character information by using packet switching ofa mobile phone and video contents by using circuit switching of themobile phone.

[0095] Here, when distributing video contents and character informationthrough different transmission paths, such a mode of use can be executedof viewing the video contents by a terminal such as a videophone andreceiving the character information through the Internet.

[0096] In a case of distributing video information and characterinformation through the common transmission path 30, it is possible toadopt a system of multiplexing the video contents and the characterinformation and distributing the multiplexed contents as will bedescribed in a second embodiment of the present invention.

[0097]FIG. 4 is a block diagram showing a structure of a contentsdistribution system according to a second embodiment of the presentinvention. According to the present embodiment, a distribution server 10a is provided with a multiplexing unit 16 and a transmission unit 17 inplace of the video transmission unit 14 and the character transmissionunit 15 of the first embodiment and a display terminal 20 a includes areception unit 27 and a demultiplexing unit 28 in place of the videoreception unit 21 and the character reception unit 24 of the firstembodiment.

[0098]FIG. 5 is a flow chart for use in explaining operation of thedistribution server 10 a of the present embodiment, while FIG. 6 is aflow chart for use in explaining operation of the distribution server 20a of the present embodiment.

[0099] With reference to FIGS. 5 and 6, the operation of the presentembodiment differs from that of the first embodiment in that, in thedistribution server 10 a, video contents coded by the video coding unit12 and character information extracted by the character extraction unit13 are multiplexed by the multiplexing unit 16 (Step 404) and themultiplexed contents are transmitted to the display terminal 20 a by thetransmission unit 17 (Step 405). In the display terminal 20 a, themultiplexed contents received by the reception unit 27 (Step 501) aredemultiplexed by the demultiplexing unit 28 into video contents andcharacter information (Step 502) which will be decoded and displayed(Steps 503 and 504).

[0100] As a multiplexing method, it is possible to multiplex informationabout video and voice and character information by using H.324/M whichis a standard for realizing videophone settled by ITU-T.

[0101] Although employed here is a system of receiving input of videocontents which are read from live video and from accumulated video bythe video input unit 11 and distributing the contents, another systemcan be similarly executed of accumulating processing results obtained bythe video coding unit 12 and the character extraction unit 13 andreading the accumulated video contents upon a user's request.

[0102] Next, description will be made of a method of distributingcharacter information generated from video contents and the videocontents in question by the distribution server 10 a and displaying thesame by the display terminal 20 a with reference to FIG. 7. Descriptionmade here is applicable not only to the second embodiment but also tothe first embodiment.

[0103] Shown in FIG. 7 is a scene where a user views and listens to anews program, in which an original image illustrated in FIG. 7(1) showsa news program with telop indicating a news headline superimposed onvideo of an announcer.

[0104] Although the description will be here made targeting telopinformation as character information, it can be similarly made targetinga common character which is not telop such as a character on a signboardin a video scene and a character multiplexed with video in databroadcasting or character broadcasting.

[0105] A display screen 20-3 a in FIG. 7 shows one example of display onthe display terminal 20 a which is obtained when video is coded andtransmitted as it is as in conventional art.

[0106] Here, the transmission path 30 is a transmission path having abit rate as low as 64 kbps to 384 kbps and for transmitting video codedby using such a transmission path 30 having a low bit rate, it isnecessary to employ the following coding methods (1) and (2) of:

[0107] (1) coding with a resolution of input video reduced, and

[0108] (2) degrading an image by reducing a bit rate necessary forcoding.

[0109] Since in general, telop of news video of television is premisedon that it is viewed and listened with a resolution of the television(e.g. 720×480), decreasing the resolution to a resolution as low as thatof QCIF (176×144) or CIF (352×288) which is often used in a mobile phonefor distributing video will result in having characters become smalleror deformed to make them hard to read.

[0110] On the other hand, degrading an image will in general result indecreasing a contrast to make a character unclear. In an MPEG as an ISOstandard, for example, since video is divided into blocks to conductcoding on a block basis, degrading an image results in making a boundarybetween blocks conspicuous and furthermore reducing a contrast in theblock. As a result, also in such a part that has to have clear contrastas a telop character, its character becomes hard to read because thecontrast is lowered.

[0111] Although FIG. 7 shows an image for use in viewing and listeningto video using a mobile phone, this problem will occur not only with amobile phone whose display screen is small but also with any displayterminal 20 a when video is distributed using the transmission path 30of a low bit rate.

[0112] This problem can be considered to derive from the fact thatnatural video such as a person and artificial character information arehandled simultaneously at the time of coding at a low bit rate. In thefirst and the second embodiments of the present invention, therefore,the distribution servers 10 and 10 a detect a character region in whichcharacters are displayed from an image of video contents, generateinformation (character information) for use in confirming the displayedcharacters and distribute the character information together with thevideo contents to the display terminals 20 and 20 a as shown in FIG.7(2) without transmitting the video contents as they are.

[0113] In other words, the video contents will be transmitted being anoriginal image as in a conventional case shown in the display screen20-3 a, while in the present embodiment (and the first embodiment),information (character information) for use in confirming characters ina character region is coded by other method than that of the videocontents and then transmitted.

[0114] It is for example possible to conduct character read with respectto video of an extracted character region, obtain text data of thedisplayed characters and transmit each character being indicated asnumerical information (character code) such as an ASCII code. A displayscreen 20-3 b shows one example of display on the display terminal 20 awhen character information is thus separately transmitted.

[0115] Transmitting character information as text data (character code)enables reduction of a volume of communication and also enables theinformation to be displayed to have an arbitrary size on the displayterminal 20 a, which allows characters to be displayed in a large sizeto be easy to read.

[0116] Processing of the character read can be executed using techniquesemployed in OCR software currently on the market and the like and otherconventional techniques.

[0117] When using character reading techniques as described above,because it is often the case that characters are erroneously read inautomatic processing of character read, transmitting not text dataobtained by character read but by an image of a character region inwhich characters are displayed as character information is alsoeffective.

[0118] In this case, with the entire image having a low resolution, bycoding only an extracted character region with a high resolution andtransmitting the coded image, characters can be displayed to be easy toread as shown on a display screen 20-3 c in FIG. 7. In the displayscreen 20-3 c in FIG. 7, video of the character region having a highresolution is displayed below the entire video contents.

[0119] Also, since as to telop information, it is a common practice tohave the same telop shown for a few seconds so as to enable viewers toread, by making use of the fact, such control can be provided astransmitting new character information only when the telop informationis changed. Although transmitting an image coded with a high resolutionas it is will result in costing a capacity of the transmission path 30,thus transmitting video of a character region with its transmissionfrequency reduced enables its necessary band to be smaller.

[0120] In addition, not transmitting a color image of an extractedcharacter region without modification but coding an image converted intoa binary image to have reduced colors in which a character is displayedin black and background in white, for example, and transmitting thecoded image enables the volume of transmission to be further reduced.

[0121] As described in the foregoing, for coding a character region tohave a high resolution, an MPEG as a moving image coding system or thelike can be used. JPEG or JPEG2000 as a still picture coding system canbe also used and for a binary image, such a coding system as JBIG can beused.

[0122] The character extraction unit 13 of the present embodimentextracts a character region, for which character region extraction,conventionally executed techniques can be used.

[0123] Since telop information, for example, has such characteristics asshown in the following (1) to (3), extraction is possible using suchcharacteristics.

[0124] (1) White characters are often used.

[0125] (2) Motion is slow.

[0126] (3) Characters appear not singly but in a group of a plurality ofcharacters.

[0127] In addition, the character extraction unit 13 can conduct notonly extraction of a character region and character read of a characterregion but also extraction of a position of a character region in videoand analysis of a document layout structure of a character region, sothat it is possible to extract a position of a character region, alayout structure or the like by the character extraction unit 13 andtransmit the same by the character transmission unit 15.

[0128] Such a position of a character region in video contents and alayout structure of a character region will be referred to as charactersubsidiary information. Character information is assumed to includecharacter subsidiary information in addition to the above-describedimage (video) of a character region, text data obtained by characterread and the like.

[0129] Although the foregoing is the description made of extraction ofcharacter information in telop information and a video scene, suchprocessing is unnecessary when characters are multiplexed with video asin data broadcasting, and the character extraction unit 13 maydemultiplex character information multiplexed in data broadcasting orthe like to extract text data.

[0130] While the description has been made with reference to FIG. 7 thatseparately transmitting character information and video informationenables users to read the character information clearly, FIG. 8 shows amethod of presenting character information to users.

[0131] A display screen 20-4 a in FIG. 8 shows a case where ordinaryvideo is displayed in the same manner as in conventional art withoutdisplaying character information etc. At this state, no otherinformation than video contents is presented to a user. There is also aconventional technique of displaying such general information as achannel number and a program name of video being displayed (by usingtext broadcasting) as shown in a display screen 20-4 b to enable a userto know what he or she now views and listens to. The display terminal 20a of the present embodiment ordinarily conducts display as shown in thedisplay screen 20-4 a and the display screen 20-4 b.

[0132] Here, when a user finds character information such as telopunclear, the user receives the character information from thedistributions server 10 a and has the same displayed independently ofvideo contents.

[0133] Although the display terminal 20 a can constantly receivecharacter information sent from the distribution server 10 a, thepresent embodiment will be described here with respect to a method ofissuing a character information transmission request to the distributionserver 10 a only when necessary to receive character information withoutconstantly receiving character information for the purpose of saving aband.

[0134] By issuing a request for character information to thedistribution server 10 a, the display terminal 20 a receivesdistribution of character information in video from the distributionserver 10 a and displays the character information.

[0135] Character information, which is transmitted as text data obtainedby character read etc. in one case and transmitted as a high-qualityimage in another case, may be appropriately used according to a capacityof the distribution server 10 a, or selection between transmission of aresult of character read and transmission of an image itself may be madeas the user issues a request for character information transmission tothe distribution server 10 a.

[0136] A display screen 20-4 c is a display example in a case wherereceived character information is subjected to character read and sentas text data, in which adjacent to video contents, its characterinformation is displayed. When program information or the like isdisplayed as shown in the display screen 20-4 b, switchedly displayingthe program information and character information allows even a smallscreen to be efficiently used.

[0137] On the display screen 20-4 c, because the amount of the characterinformation is small, video information and character information aredisplayed to be arranged like tiles, while when character information islarge, characters may be displayed in a vertical direction, a horizontaldirection or both directions by scrolling.

[0138] It is also possible to arrange the information, not like tiles asshown in the display screen 20-4 c, but so as to have part of characterinformation overlapping video. Moreover, when a position of characterinformation in video is received as character subsidiary informationfrom the distribution server 10 a, the character information may bedisplayed superimposed on a position of the original video as shown in adisplay screen 20-4 f.

[0139] Next, description will be made of processing to be conducted whenthe distribution server 10 a detects a plurality of regions in whichcharacters are displayed in video contents.

[0140] In this case, the distribution server 10 a can distribute all thecharacter information in the detected video contents to the displayterminal 20 a and also can distribute only character information in aregion designated by a user.

[0141] One embodiment of the operation conducted in this case will bedescribed. The distribution server 10 a transmits character informationso as to include character subsidiary information such as layoutinformation about a character and a sentence in each region and positioninformation of each region detected to the display terminal 20 a. Then,by the display terminal 20 a, a user selects a region whose characterinformation is desired by the user using the character subsidiaryinformation and notifies the distribution server 10 a of the region.Then, the distribution server 10 a generates character information fromthe region selected by the user and notified by the display terminal 20a and distributes the information to the display terminal 20 a.

[0142] When there is no character subsidiary information, it is forexample possible to instruct the distribution server 10 a by the displayterminal 20 a to switch character information and sequentially switchthe information to select information with reference to the contents ofeach character information.

[0143] Thus, not by distributing all the character information to thedisplay terminal 20 a but based on a request for character informationtransmission such as an instruction to switch desired characterinformation notified by the display terminal 20 a or characterinformation to be distributed, the distribution server 10 a is allowedto distribute only character information required in video contents.

[0144] In this case, while the distribution server 10 a may firstdistribute character information of a character region first detectedout of an image of video contents to the display terminal 20 a and havethe information first displayed on the display terminal 20 a, it maymore preferably determine an order of distribution based on the contentsof character information about a position of display in video contentsand a result of character read.

[0145] Possible method is most preferentially distributing characterinformation of characters which are horizontally written at the centerof the lower part of video contents because they are highly probablytelop and on the other hand, with characters indicated at an upper leftor right corner of video contents within a narrow range, preferentiallydistributing other character information than that of these charactersbecause they are highly probably an indication of current time andtherefore of little importance.

[0146] A further method is possible of distributing all characterinformation from the distribution server 10 a to the display terminal 20a and select character information to be displayed on the side of thedisplay terminal 20 a.

[0147] Also as shown in a display screen 20-4 d, the distribution server10 a may automatically translate text data of its read characterinformation into other language designated, distribute the translationas character information to the display terminal 20 a and have theterminal display the same.

[0148] By employing conventional techniques used in translation softwareor the like, the automatic translation is possible between variouslanguages such as from Japanese to English as shown in the displayscreen 20-4 d and from English to Japanese. By thus automaticallytranslating and distributing extracted character information, service ofproviding video contents in various languages can be simplified. Methodof displaying a translation is the same as that of the display screen20-4 c.

[0149] Next, as shown on a display screen 20-4 e, also when thedistribution server 10 a distributes character information as an image(video) of a region in which its characters are displayed, the characterinformation can be displayed in other window than that of the videocontents similarly to the case of the display screen 20-4 c.

[0150] When an image of character information larger in size than ascreen is distributed, the display terminal 20 a can reduce the image ofthe character information and display the reduced image or when a userwants to view details, the terminal can expand the image in a verticaldirection or a horizontal direction by scrolling to display the details.

[0151] When character information includes character subsidiaryinformation such as layout information, the display terminal 20 a canregenerate an image of a character region so as to be easy to read basedon the information and present the regenerated image.

[0152] Also when distributing character information as an image, asshown on the display screen 20-4 f, the image of the characterinformation can be displayed not in other region than that of videocontents but in the same region as that of video with the characterinformation superimposed on the video. By displaying characterinformation so as to be superimposed on a character region of originalvideo contents, in particular, image of the character information can bedisplayed to be easy to read.

[0153] Since an image of character information distributed has a higherresolution than that of original video contents in general, it ispossible, similarly to the case of the display screen 20-4 e asdescribed above, to first reduce the image of the distributed characterinformation, superimpose the reduced image on the original videocontents and display the overlapped image and when necessary, releasethe reduction (or change the size to a designated size) and display therestored image while scrolling.

[0154] As shown in the display screen 20-4 d, character informationsubjected to character read and translated into other language can bedisplayed in other window than that of video contents, which can be alsosimilarly displayed being superimposed on the video contents as shown ina display screen 20-4 g.

[0155] This is applicable to superimposition of video contents of aforeign picture and when a user wants to concentrate on a movie, thisprevents the user from losing concentration while watching other window.For realizing the application, it is for example possible to directlysuperimpose character information of a translation to be distributed intext data on video, or generate and display a character image from thetext data of the translation according to a size of a character region.

[0156] It is further possible not to distribute a result obtained bycharacter read by the distribution server 10 a as text data but togenerate a character image indicative of characters of the text data anddistribute the image as character information to the display terminal 20a. In this case, the display terminal 20 a is allowed to display acharacter clearly simply by displaying images of the received characterinformation so as to overlap with each other.

[0157] In a case of such video contents as video for language learningand of foreign films, such is demanded as erasing superimpositiondisplayed in the video contents.

[0158] In this case, as shown in a display screen 20-4 h, based onposition information of a region where characters are displayed in videocontents which position is indicated by distributed character subsidiaryinformation, the display terminal 20 a can provide a user with characterinformation with the region in question erased.

[0159] Also in this case, when such a need occurs of knowing an answerduring language study, the display terminal 20 a can present characterinformation to a user while displaying, erasing or switching thecharacter information by the manner as described with respect to thedisplay screens 20-4 a to 20-4 g according to the user's operation.

[0160] Although the foregoing methods of presenting video contents andcharacter information according to the first and the second embodimentshave been described with respect to a case, as an example, where thedisplay terminals 20 and 20 a are portable communication terminals suchas mobile phones, the display terminal 20 a is not necessarily limitedto a mobile phone. While the contents distribution system of the presentinvention is effective in particular when the display terminals 20 and20 a as distribution destinations have a display unit whose area issmall, distribution to other terminals such as a personal computer and anotebook computer is similarly possible.

[0161] As described in the foregoing, the contents distribution systemsof the first and the second embodiments enable video contentsdistributed at a low bit rate to be presented to a user with charactersclearly displayed by a reception side display terminal.

[0162] Next, a third embodiment of the present invention will bedescribed. FIG. 9 is a block diagram showing a structure of a contentsdistribution system according to the third embodiment of the presentinvention. The present embodiment is to extract and display characterinformation only by using a display terminal 20 b without using thedistribution server 10.

[0163]FIG. 10 is a flow chart for use in explaining operation of thedisplay terminal 20 b according to the present embodiment.

[0164] The display terminal 20 b of the present embodiment, which is aportable terminal for receiving broadcasting video such as televisionbroadcasting, receives, by means of the video reception unit 21, videocontents such as a television program being on air from an externalbroadcasting station 40 or the like through radio wave (Step 601).Decode the received video contents by means of the video decoding unit22 (Step 602), generate its character information by means of acharacter extraction unit 29 (Step 603) and display the video contentsand its character information by means of the video display unit 23(Step 604).

[0165] Since the display terminal 20 b is premised on portable use, itis only capable of displaying an image with a low resolution, so thatthe video display unit 23 reduces video contents and displays thereduced contents. At this time, the reduced video contents might havecharacters of telop or the like be unclear or distorted in some cases.

[0166] On the other hand, since video is decoded by the video decodingunit 22 to have a general resolution, by extracting a character regionby means of the character extraction unit 29 by using the video with ageneral resolution and displaying character information by means of thecharacter display unit 26, video contents are presented to a user so asto be easy to understand. In addition, the character extraction unit 29is capable not only of extracting a character region but also ofconducting character read to obtain text data of a character to bedisplayed. In this case, the obtained text data is displayed by thecharacter display unit 26.

[0167] The method of displaying character information conducted by thedisplay terminal 20 b according to the present embodiment can beexecuted by the same manner as those of the above-described first andsecond embodiments.

[0168] As described in the foregoing, according to the presentembodiment, when the display terminal 20 b has a processing capacitysufficient for conducting character extraction, the display terminal 20b itself can extract character information from video contents such astelevision broadcasting and display the extracted character informationwith a high resolution without requiring a distribution server. As aresult, it is possible to present video contents even on the displayterminal 20 b having a small screen such as a portable terminal to auser so as to be easy to understand similarly to the display terminals20 and 20 a of the first and second embodiments.

[0169] Next, a fourth embodiment of the present invention will bedescribed. FIG. 11 is a block diagram showing a structure of a contentsdistribution system according to the fourth embodiment of the presentinvention.

[0170] Although according to the third embodiment, the display terminal20 b directly receives video and also extracts a character region, sincea portable apparatus has a low processing capacity in general, it mighthave difficulty in extracting a character region.

[0171]FIG. 12 is a flow chart for use in explaining operation of adistribution server 10 c.

[0172] According to the present embodiment, therefore, the distributionserver 10 c receives, at the video input unit 11, video contents of thesame program as that received by a display terminal 20 c from theexternal broadcasting station 40 (Step 701), extracts its characterinformation by means of the character extraction unit 13 (Step 702) andtransmits the character information to the display terminal 20 c bymeans of the character transmission unit 15 (Step 703). The displayterminal 20 c, similarly to the first and the second embodiments,receives, at the character reception unit 24, character informationdistributed from the distribution server 10 c, conducts necessarydecoding processing at the character decoding unit 25 and displays thecharacter information by means of the character display unit 26.

[0173] On the other hand, similarly to the third embodiment, videocontents are received from other unit such as the broadcasting station40 or the like than the distribution server 10 c by means of the videoreception unit 21, subjected to necessary decoding processing by thevideo decoding unit 22 and displayed by the video display unit 23.

[0174] The method of displaying character information by the displayterminal 20 c according to the present embodiment can be executed by thesame manner as those of the above-described first and secondembodiments.

[0175] As described in the foregoing, the present embodiment enables, inaddition to the effect attained by the third embodiment, even thedisplay terminal 20 c having difficulty in conducting processing ofextracting a character region to display character information. Inaddition, by distributing only character information by the distributionserver 10 c and receiving video contents by the display terminal 20 cfrom other unit such as the broadcasting station 40, the same effectsattained by the contents distribution systems according to the first andthe second embodiments can be realized.

[0176] Moreover, by receiving video information whose volume of data isin general large by directly using radio wave without receiving thevideo from the distribution server 10 c, costs for data communicationcan be suppressed to distribute character information more efficientlythan by the first and the second embodiments.

[0177] Although each of the above-described embodiments employs a systemin which each of the display terminals 20, 20 a, 20 b and 20 csimultaneously displays video contents and its character information,the terminal may display only character information and not videocontents. As a result, character information of video contents can bedisplayed with less volume of communication.

[0178] In the contents distribution systems according to theabove-described embodiments, the functions of the video input unit 11,the video coding unit 12, the character extraction unit 13, the videotransmission unit 14, the character transmission unit 15, themultiplexing unit 16 and the transmission unit 17 in each of thedistribution servers 10, 10 a and 10 c, the functions of the videoreception unit 21, the video decoding unit 22, the video display unit23, the character reception unit 24, the character decoding unit 25, thecharacter display unit 26, the reception unit 27, the demultiplexingunit 28 and the character extraction unit 29 in each of the displayterminals 20, 20 a, 20 b and 20 c, and other functions can be realizednot only by hardware but also by loading contents distribution programs90, 90 a, 90 c, 91, 91 a, 91 b and 91 c as computer programs having therespective functions into a memory of a computer processing device. Thecontents distribution programs 90, 90 a, 90 c, 91, 91 a, 91 b and 91 care stored in a recording medium such a magnetic disc or a semiconductormemory. Then, loading the programs from the recording medium into thecomputer processing device to control operation of the computerprocessing device realizes each of the above-described functions.

[0179] Although the present invention has been described with respect tothe preferred modes and embodiments in the foregoing, the presentinvention is not necessarily limited to the above-described modes adembodiments and can be implemented in variation within a scope of itstechnical idea.

[0180] As described in the foregoing, the present invention enables evenvideo contents distributed at a low bit rate to be presented to a userso as to be easy to understand by extracting character information fromthe video contents at a distribution server and, independently of thevideo contents, distributing the same as text data or as an image codedby using high-quality coding method.

[0181] Therefore, a display terminal requires no capability ofprocessing character extraction and even a display terminal having anarrow display screen such as a portable communication terminal isallowed to display characters in video contents clearly and present thecontents of the video contents to be easy to understand to a user.

[0182] Although the invention has been illustrated and described withrespect to exemplary embodiment thereof, it should be understood bythose skilled in the art that the foregoing and various other changes,omissions and additions may be made therein and thereto, withoutdeparting from the spirit and scope of the present invention. Therefore,the present invention should not be understood as limited to thespecific embodiment set out above but to include all possibleembodiments which can be embodies within a scope encompassed andequivalents thereof with respect to the feature set out in the appendedclaims.

1. A contents distribution system for distributing contents from adistribution server to a display terminal, wherein said distributionserver detects a region in which a character is displayed from an imageof video contents, generates character information for use in confirmingsaid character displayed in said region detected and distributes saidcharacter information generated to said display terminal.
 2. Thecontents distribution system as set forth in claim 1, wherein saiddistribution server generates an image of said region detected as thecharacter information of said video contents.
 3. The contentsdistribution system as set forth in claim 1, wherein said distributionserver generates text data of the character displayed in said regiondetected as the character information of said video contents bycharacter read.
 4. The contents distribution system as set forth inclaim 1, wherein when a plurality of regions in which characters aredisplayed are detected from the image of said video contents, saiddistribution server accepts designation of said region from said displayterminal and distributes said character information generated from saidregion designated to said display terminal.
 5. The contents distributionsystem as set forth in claim 1, wherein said distribution serverdistributes said video contents to said display terminal simultaneouslywith the character information of said video contents, and said displayterminal presents the character information of said video contentsreceived from said distribution server together with said video contentsreceived simultaneously.
 6. The contents distribution system as setforth in claim 5, wherein said distribution server multiplexes thecharacter information of said video contents and said video contents anddistributes the multiplexed contents to said display terminal.
 7. Thecontents distribution system as set forth in claim 1, wherein saiddisplay terminal receives, from said distribution server, characterinformation of said video contents received from an externalbroadcasting station and presents the character information of saidvideo contents together with said video contents.
 8. The contentsdistribution system as set forth in claim 1, wherein the characterinformation of said video contents includes character subsidiaryinformation indicative of features of the character displayed in theimage of said video contents, and said display terminal presents thecharacter information of said video contents received from saiddistribution server based on said character subsidiary informationincluded in said character information.
 9. The contents distributionsystem as set forth in claim 8, wherein the character subsidiaryinformation of said video contents includes information about aposition, in the image of said video contents, of said region detectedfrom said image.
 10. The contents distribution system as set forth inclaim 8, wherein the character subsidiary information of said videocontents includes information about a layout structure of the characterdisplayed in the image of said video contents.
 11. A distribution serverfor distributing contents to a display terminal, comprising: means fordetecting a region in which a character is displayed from an image ofvideo contents, means for generating character information for use inconfirming said character displayed in said region detected, and meansfor distributing said character information generated to said displayterminal.
 12. The server as set forth in claim 11, further comprising:means for, when a plurality of regions in which characters are displayedare detected from the image of said video contents, acceptingdesignation of said region from said display terminal, therebydistributing said character information generated in said regiondesignated to said display terminal.
 13. The server as set forth inclaim 11, further comprising means for distributing said video contentsto said display terminal simultaneously with the character informationof said video contents.
 14. The server as set forth in claim 13, furthercomprising means for multiplexing the character information of saidvideo contents and said video contents and distributing the multiplexedcontents to said display terminal.
 15. The server according claim 13,further comprising: means for generating an image of said regiondetected as the character information of said video contents, and meansfor reducing the size of an image of said video contents to bedistributed to said display terminal to a designated size, therebydistributing said image generated as said character information withquality higher than the quality of said video contents whose image sizeis reduced to said display terminal together with said video contentsreduced.
 16. The server as set forth in claim 11, further comprisingmeans for generating an image of said region detected as the characterinformation of said video contents.
 17. The server as set forth in claim11, further comprising means for generating an image obtained by makingsaid region detected into a binary image as the character information ofsaid video contents.
 18. The server as set forth in claim 11, furthercomprising means for generating text data of the character displayed insaid region detected as the character information of said video contentsby character read.
 19. The server as set forth in claim 11, furthercomprising: means for obtaining text data of the character displayed insaid region detected by character read, and means for generating atranslation which is obtained by translating said text data obtained bysaid character read into a designated language as the characterinformation of said video contents.
 20. The server as set forth in claim11, further comprising: means for identifying features of a characterdisplayed in the image of said video contents, thereby distributing, ascharacter subsidiary information, information about features of saidcharacter identified so as to be included in the character informationof said video contents to said display terminal.
 21. The server as setforth in claim 11, further comprising: means for recording said videocontents and the character information of said video contents, and meansresponsive to a request from said display terminal for distributing saidvideo contents and the character information of said video contentsrequested to said display terminal.
 22. A display terminal forpresenting contents distributed from a distribution server, comprising:means for receiving character information for use in confirming acharacter displayed in an image of video contents from said distributionserver, and means for presenting said character information received.23. The display terminal as set forth in claim 22, further comprising:means for accepting, from said distribution server, a notification thata plurality of regions in which characters are displayed are detectedfrom the image of said video contents, and means for notifying saidregion selected by a user from among said plurality of regions detectedto said distribution server, thereby receiving the character informationfor use in confirming a character displayed in said region selected fromsaid distribution server.
 24. The display terminal as set forth in claim22, wherein the character information of said video contents is an imageof a region in which a character is displayed in the image of said videocontents.
 25. The display terminal as set forth in claim 24, furthercomprising means for obtaining, from the image of said characterinformation by character read, text data of a character indicated insaid character information received and presenting the obtained data.26. The display terminal as set forth in claim 22, wherein the characterinformation of said video contents is text data of a character displayedin the image of said video contents.
 27. The display terminal as setforth in claim 22, further comprising: means for simultaneouslyreceiving the character information of said video contents and the videocontents in question from said distribution server, and means forpresenting both said character information and said video contentsreceived.
 28. The display terminal as set forth in claim 27, furthercomprising means for receiving the character information of said videocontents and the video content in question which are multiplexed anddistributed from said distribution server.
 29. The display terminal asset forth in claim 22, further comprising means for receiving, from saiddistribution server, said character information of said video contentsreceived from an external broadcasting station and presenting thecharacter information of said video contents together with said videocontents.
 30. The display terminal as set forth in claim 22, wherein thecharacter information of said video contents includes charactersubsidiary information indicative of features of the character displayedin the image of said video contents, and which further comprises: meansfor presenting the character information of said video contents receivedfrom said distribution server based on said character subsidiaryinformation included in said character information.
 31. The displayterminal as set forth in claim 30, wherein said character subsidiaryinformation includes information about a position, in the image of saidvideo contents, of a region in which a character in said image isdisplayed, and which further comprises: means for presenting said videocontents with the region where said character is displayed which isindicated in said character subsidiary information erased.
 32. Thedisplay terminal as set forth in claim 22, further comprising means forinstructing said distribution server to transmit or not to transmit saidcharacter information.
 33. A display terminal for presenting videocontents, comprising: means for detecting a region in which a characteris displayed from an image of video contents, means for generatingcharacter information for use in confirming said character displayed insaid region detected, and means for presenting said characterinformation generated.
 34. The display terminal as set forth in claim33, further comprising means for presenting said character informationof the video contents in question together with said video contents. 35.The display terminal as set forth in claim 22, further comprising meansfor simultaneously displaying the character information of said videocontents and said video contents in separate windows on a displayscreen.
 36. The display terminal as set forth in claim 22, furthercomprising means for simultaneously displaying, in an area in which saidvideo contents are displayed on the display screen, characterinformation of said video contents.
 37. The display terminal as setforth in claim 22, which is a portable communication terminal.
 38. Acontents distribution program for distributing contents to a displayterminal by controlling a computer, comprising the functions of:detecting a region in which a character is displayed from an image ofvideo contents, generating character information for use in confirmingsaid character displayed in said region detected, and distributing saidcharacter information generated to said display terminal together withsaid video contents.
 39. A contents distribution program for presentingcontents distributed from a distribution server by controlling acomputer, comprising the functions of: receiving character informationfor use in confirming a character displayed in an image of videocontents from said distribution server together with said videocontents, and presenting said character information received togetherwith said video contents received.